Police say it's a growing trend and that young girls often don't realize they are victims because the traffickers convince them they are offenders.

Now, a federal grant will help combat the problem in Northern Virginia.

Prostitution or human trafficking doesn't always look like you think it does. It may be going on in your neighborhood, with local high school girls being sold, says Fairfax county Detective Bill Woolf.

"I've seen victims from several high schools throughout Northern Virginia. I would say that our kids in each and every high school are vulnerable to the trafficker's deceptions," said Woolf.

Victims come from all walks of life, from rich families to poor families. One girls had a 3.9 grade point average. But they do have common characteristics that make them vulnerable to the traffickers.

They target teenage girls, and sometimes boys, who have low self esteem, no self identity, don't participate in sports or other activities, and kids who don't have strong family connections.

Traffickers often trick girls like this using what's called the "boyfriend" method, says Detective Woolf.

"It's not appropriate for a 26-year-old boy to date a 14-year-old girl. It's not appropriate for him to buy her things because this might be him grooming her for some type of exploitation," said Woolf.

Today, The Northern Virginia Task Force received a $1 million grant from the Justice Department to combat human trafficking. Half of it will go to the Polaris Project which helps victims.

"Last year in 2012, we served 88 survivors of trafficking from the region, 25 whom were children," said Bradley Myles, the CEO and Executive Director of the Polaris Project.

The other half goes to the Fairfax County police department to coordinate local, state and federal efforts.

"We have upped the penalties. We've gotten more aggressive with legislation to make sure we can punish them more aggressively so that we changed this calculus for the gang members. We make it more expensive for them; we make it riskier for them. And this grant will increase our ability to find and prosecute them," said Virginia Attorney General Ken Cuccinelli.

Over the past two years, The U.S. Attorney's office for has successfully prosecuted 24 federal cases against 57 defendants engaged in human trafficking in Northern Virginia. The cases involved 388 victims of sexual exploitation, 38 were children.

If you know someone who may be caught in human trafficking, here's the national hotline number, 1-888-3737-888.